Извлечь только год из даты

ALTER SESSION SET NLS_DATE_FORMAT = 'DD-MM-RRRR';

SELECT prd_type_id, YEAR, MONTH, sales_amount
FROM all_sales
WHERE prd_type_id BETWEEN 1 AND 2 AND emp_id = 21
MODEL
PARTITION BY (prd_type_id)
DIMENSION BY (MONTH, YEAR)
MEASURES (amount sales_amount) (
sales_amount[1, 2004] = sales_amount[1, 2003],
sales_amount[2, 2004] = sales_amount[2, 2003] + sales_amount[3, 2003],
sales_amount[3, 2004] = ROUND(sales_amount[3, 2003] * 1.25, 2) )
ORDER BY prd_type_id, YEAR, MONTH;

SELECT to_char(sysdate, 'yyyy')   -- при необходимости to_number( to_char ... )
FROM dual

SELECT EXTRACT(YEAR FROM sysdate)
FROM dual

CREATE TABLE Arsti_new2(
Arsta_ID NUMBER PRIMARY KEY,
Arsta_vards varchar2(10),
Arsta_uzvards varchar2(15),
Nodalas_num NUMBER,
dzimsanas_datums DATE,
Alga NUMBER);

ALTER SESSION SET NLS_DATE_FORMAT = 'DD-MM-RRRR';
INSERT INTO arsti_new2(arsta_id,arsta_uzvards,arsta_vards, nodalas_num,dzimsanas_datums,alga) VALUES(1,'Briķis','Jānis',NULL,TO_DATE('03-04-1986','DD-MM-RRRR'),626);
.............
.............
............

SELECT arsta_ID, dzimsanas_datums, alga
FROM arsti_new2
model
partition BY(arsta_id)
dimension BY(только год или месяц и год вытащить из dzimsanas_datums)
measures(alga alga) (
algas[год или месяц и год] = algas[......
..........

CREATE VIEW artsi_new2_XXX AS
  SELECT
    *,
    to_number(to_char(dzimsanas_datums, 'yyyy')) AS dzimsanas_datums_year,
    to_number(to_char(dzimsanas_datums, 'mm')) AS dzimsanas_datums_month
  FROM artsi_new2